message reports that the chassis process (chassisd) detected the indicated error condition for the indicated power entry module (PEM).

When a  CHASSISD_PEM_INPUT_BAD event occurs, messages similar to the following are reported:

These logs indicate a problem with the input voltage to the PEM, which may be due to a flipped circuit breaker, an uncabled PEM, a seating problem with the PEM unit, an incorrect voltage setting, or an actual hardware failure.

Perform these steps to determine the cause and resolve the problem (if any). Continue through each step until the problem is resolved.

1. Collect the show command output.

Capture the output to a file (in case you have to open a technical support case). To do this, configure each SSH client/terminal emulator to log your session.

2. Analyze the show command output.

In the ‘show log messages’ output, review the events that occurred at or just before the appearance of the

message. Frequently these events help identify the cause.

3. During a maintenance window, as it will impact transit traffic, try the following:

  • Check if the chassis requires redundant PEM units to be present. If so, ensure that they are present and inserted in the correct slots. For example, certain platforms may allow four PEM modules, but only two are required. However, if only two are used, they need to be in specific slots. The number of available slots, minimum PEM units required, and which slots must be populated first are all platform-dependent information. See the Hardware Documentation for your product in the Technical Documentation for more information.
  • Check the voltage type and verify that the value is correct for that PEM unit (that is, 120 volt vs. 240 volt, DC vs. AC).
  • Verify that the circuit breaker has not been tripped. You may need to purposely flip it off and on again to make sure that it is on. Note that these alarms and logs might be seen if the circuit breaker is turned off, or if there is no power feed connected.
  • Try reseating the PEM unit.
  • Try swapping with a spare, if available, or try swapping two PEM units in their respective slots to see if the message follows the unit or the slot.

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